
/*
  +------------------------------------------------------------------------+
  | Phalcon Framework                                                      |
  +------------------------------------------------------------------------+
  | Copyright (c) 2011-2014 Phalcon Team (http://www.phalconphp.com)       |
  +------------------------------------------------------------------------+
  | This source file is subject to the New BSD License that is bundled     |
  | with this package in the file docs/LICENSE.txt.                        |
  |                                                                        |
  | If you did not receive a copy of the license and are unable to         |
  | obtain it through the world-wide-web, please send an email             |
  | to license@phalconphp.com so we can send you a copy immediately.       |
  +------------------------------------------------------------------------+
  | Authors: Andres Gutierrez <andres@phalconphp.com>                      |
  |          Eduar Carvajal <eduar@phalconphp.com>                         |
  |          Vladimir Kolesnikov <vladimir@extrememember.com>              |
  |          ZhuZongXin <dreamsxin@qq.com>                                 |
  +------------------------------------------------------------------------+
*/

#include "kernel/murmurhash.h"

#define BIG_CONSTANT(x) (x##ULL)

zend_always_inline uint32_t rotl32(uint32_t x, int8_t r)
{
	return (x << r) | (x >> (32 - r));
}

#define ROTL32(x,y) rotl32(x,y)

zend_always_inline uint32_t getblock32(const uint32_t * p, int i)
{
	return p[i];
}

zend_always_inline uint32_t fmix32(uint32_t h)
{
	h ^= h >> 16;
	h *= 0x85ebca6b;
	h ^= h >> 13;
	h *= 0xc2b2ae35;
	h ^= h >> 16;

	return h;
}

void MurmurHash3_x86_32(const void * key, int len, uint32_t seed, void * out)
{
	const uint8_t * data = (const uint8_t*)key;
	const int nblocks = len / 4;

	uint32_t h1 = seed;

	const uint32_t c1 = 0xcc9e2d51;
	const uint32_t c2 = 0x1b873593;

	//----------
	// body

	const uint32_t * blocks = (const uint32_t *)(data + nblocks*4);

	int i;
	for(i = -nblocks; i; i++)
	{
		uint32_t k1 = getblock32(blocks,i);

		k1 *= c1;
		k1 = ROTL32(k1,15);
		k1 *= c2;

		h1 ^= k1;
		h1 = ROTL32(h1,13); 
		h1 = h1*5+0xe6546b64;
	}

	const uint8_t * tail = (const uint8_t*)(data + nblocks*4);

	uint32_t k1 = 0;

	switch(len & 3)
	{
		case 3: k1 ^= tail[2] << 16;
		case 2: k1 ^= tail[1] << 8;
		case 1: k1 ^= tail[0];
			k1 *= c1; k1 = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
	};

	h1 ^= len;

	h1 = fmix32(h1);

	*(uint32_t*)out = h1;
}

void MurmurHash3_x86_128(const void * key, const int len, uint32_t seed, void * out)
{
	const uint8_t * data = (const uint8_t*)key;
	const int nblocks = len / 16;

	uint32_t h1 = seed;
	uint32_t h2 = seed;
	uint32_t h3 = seed;
	uint32_t h4 = seed;

	const uint32_t c1 = 0x239b961b; 
	const uint32_t c2 = 0xab0e9789;
	const uint32_t c3 = 0x38b34ae5; 
	const uint32_t c4 = 0xa1e38b93;

	const uint32_t * blocks = (const uint32_t *)(data + nblocks*16);

	int i;
	for(i = -nblocks; i; i++)
	{
		uint32_t k1 = getblock32(blocks,i*4+0);
		uint32_t k2 = getblock32(blocks,i*4+1);
		uint32_t k3 = getblock32(blocks,i*4+2);
		uint32_t k4 = getblock32(blocks,i*4+3);

		k1 *= c1; k1  = ROTL32(k1,15); k1 *= c2; h1 ^= k1;

		h1 = ROTL32(h1,19); h1 += h2; h1 = h1*5+0x561ccd1b;

		k2 *= c2; k2  = ROTL32(k2,16); k2 *= c3; h2 ^= k2;

		h2 = ROTL32(h2,17); h2 += h3; h2 = h2*5+0x0bcaa747;

		k3 *= c3; k3  = ROTL32(k3,17); k3 *= c4; h3 ^= k3;

		h3 = ROTL32(h3,15); h3 += h4; h3 = h3*5+0x96cd1c35;

		k4 *= c4; k4  = ROTL32(k4,18); k4 *= c1; h4 ^= k4;

		h4 = ROTL32(h4,13); h4 += h1; h4 = h4*5+0x32ac3b17;
	}

	const uint8_t * tail = (const uint8_t*)(data + nblocks*16);

	uint32_t k1 = 0;
	uint32_t k2 = 0;
	uint32_t k3 = 0;
	uint32_t k4 = 0;

	switch(len & 15)
	{
		case 15: k4 ^= tail[14] << 16;
		case 14: k4 ^= tail[13] << 8;
		case 13: k4 ^= tail[12] << 0;
			   k4 *= c4; k4  = ROTL32(k4,18); k4 *= c1; h4 ^= k4;

		case 12: k3 ^= tail[11] << 24;
		case 11: k3 ^= tail[10] << 16;
		case 10: k3 ^= tail[ 9] << 8;
		case  9: k3 ^= tail[ 8] << 0;
			k3 *= c3; k3  = ROTL32(k3,17); k3 *= c4; h3 ^= k3;

		case  8: k2 ^= tail[ 7] << 24;
		case  7: k2 ^= tail[ 6] << 16;
		case  6: k2 ^= tail[ 5] << 8;
		case  5: k2 ^= tail[ 4] << 0;
			k2 *= c2; k2  = ROTL32(k2,16); k2 *= c3; h2 ^= k2;

		case  4: k1 ^= tail[ 3] << 24;
		case  3: k1 ^= tail[ 2] << 16;
		case  2: k1 ^= tail[ 1] << 8;
		case  1: k1 ^= tail[ 0] << 0;
			k1 *= c1; k1  = ROTL32(k1,15); k1 *= c2; h1 ^= k1;
	};

	h1 ^= len; h2 ^= len; h3 ^= len; h4 ^= len;

	h1 += h2; h1 += h3; h1 += h4;
	h2 += h1; h3 += h1; h4 += h1;

	h1 = fmix32(h1);
	h2 = fmix32(h2);
	h3 = fmix32(h3);
	h4 = fmix32(h4);

	h1 += h2; h1 += h3; h1 += h4;
	h2 += h1; h3 += h1; h4 += h1;

	((uint32_t*)out)[0] = h1;
	((uint32_t*)out)[1] = h2;
	((uint32_t*)out)[2] = h3;
	((uint32_t*)out)[3] = h4;
}

#ifdef ZEND_ENABLE_ZVAL_LONG64

zend_always_inline uint64_t rotl64(uint64_t x, int8_t r)
{
	return (x << r) | (x >> (64 - r));
}

# define ROTL64(x,y) rotl64(x,y)

zend_always_inline uint64_t getblock64 (const uint64_t* p, int i)
{
	return p[i];
}

zend_always_inline uint64_t fmix64 ( uint64_t k )
{
	k ^= k >> 33;
	k *= BIG_CONSTANT(0xff51afd7ed558ccd);
	k ^= k >> 33;
	k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53);
	k ^= k >> 33;

	return k;
}

void MurmurHash3_x64_128(const void* key, const int len, const uint32_t seed, void* out)
{
	const uint8_t * data = (const uint8_t*)key;
	const int nblocks = len / 16;

	uint64_t h1 = seed;
	uint64_t h2 = seed;

	const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);
	const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);

	const uint64_t * blocks = (const uint64_t *)(data);

	int i;
	for(i = 0; i < nblocks; i++)
	{
		uint64_t k1 = getblock64(blocks,i*2+0);
		uint64_t k2 = getblock64(blocks,i*2+1);

		k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
		h1 = ROTL64(h1,27); h1 += h2; h1 = h1*5+0x52dce729;

		k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;
		h2 = ROTL64(h2,31); h2 += h1; h2 = h2*5+0x38495ab5;
	}

	const uint8_t * tail = (const uint8_t*)(data + nblocks*16);

	uint64_t k1 = 0;
	uint64_t k2 = 0;

	switch(len & 15)
	{
		case 15: k2 ^= ((uint64_t)tail[14]) << 48;
		case 14: k2 ^= ((uint64_t)tail[13]) << 40;
		case 13: k2 ^= ((uint64_t)tail[12]) << 32;
		case 12: k2 ^= ((uint64_t)tail[11]) << 24;
		case 11: k2 ^= ((uint64_t)tail[10]) << 16;
		case 10: k2 ^= ((uint64_t)tail[ 9]) << 8;
		case  9: k2 ^= ((uint64_t)tail[ 8]) << 0;
			k2 *= c2; k2  = ROTL64(k2,33); k2 *= c1; h2 ^= k2;

		case  8: k1 ^= ((uint64_t)tail[ 7]) << 56;
		case  7: k1 ^= ((uint64_t)tail[ 6]) << 48;
		case  6: k1 ^= ((uint64_t)tail[ 5]) << 40;
		case  5: k1 ^= ((uint64_t)tail[ 4]) << 32;
		case  4: k1 ^= ((uint64_t)tail[ 3]) << 24;
		case  3: k1 ^= ((uint64_t)tail[ 2]) << 16;
		case  2: k1 ^= ((uint64_t)tail[ 1]) << 8;
		case  1: k1 ^= ((uint64_t)tail[ 0]) << 0;
			k1 *= c1; k1  = ROTL64(k1,31); k1 *= c2; h1 ^= k1;
	};

	h1 ^= len; h2 ^= len;

	h1 += h2;
	h2 += h1;

	h1 = fmix64(h1);
	h2 = fmix64(h2);

	h1 += h2;
	h2 += h1;

	((uint64_t*)out)[0] = h1;
	((uint64_t*)out)[1] = h2;
}

zend_ulong MurmurHash2(const void* key, zend_ulong len, uint32_t seed)
{
	const unsigned char* data2;
	const zend_ulong m = sizeof(zend_ulong) == 8 ? 0xc6a4a7935bd1e995 : 0;
	const int r = 47;

	zend_ulong h = seed ^ (len * m);

	const zend_ulong* data = (const zend_ulong *)key;
	const zend_ulong* end = data + (len / 8);

	while (data != end)
	{
		zend_ulong k = *data++;

		k *= m;
		k ^= k >> r;
		k *= m;

		h ^= k;
		h *= m;
	}

	data2 = (const unsigned char*)data;

	switch (len & 7)
	{
		case 7: h ^= (zend_ulong)data2[6] << 48;
		case 6: h ^= (zend_ulong)data2[5] << 40;
		case 5: h ^= (zend_ulong)data2[4] << 32;
		case 4:	h ^= (zend_ulong)data2[3] << 24;
		case 3:	h ^= (zend_ulong)data2[2] << 16;
		case 2:	h ^= (zend_ulong)data2[1] << 8;
		case 1:	h ^= (zend_ulong)data2[0];
		h *= m;
	};

	h ^= h >> r;
	h *= m;
	h ^= h >> r;

	return h;
}

#else

zend_ulong MurmurHash2(const void* key, zend_ulong len, uint32_t seed)
{
	/* 'm' and 'r' are mixing constants generated offline.
	   They're not really 'magic', they just happen to work well. */
	const zend_ulong m = 0x5bd1e995;
	const int r = 24;

	zend_ulong h = seed ^ len;

	/* Mix 4 bytes at a time into the hash */
	const unsigned char * data = (const unsigned char *)key;

	while (len >= 4)
	{
		zend_ulong k = *(zend_ulong *)data;

		k *= m;
		k ^= k >> r;
		k *= m;

		h *= m;
		h ^= k;

		data += 4;
		len -= 4;
	}

	/* Handle the last few bytes of the input array */
	switch (len)
	{
		case 3: h ^= data[2] << 16;
		case 2: h ^= data[1] << 8;
		case 1:	h ^= data[0];
		h *= m;
	};

	/* Do a few final mixes of the hash to ensure the last few
	   bytes are well-incorporated. */

	h ^= h >> 13;
	h *= m;
	h ^= h >> 15;

	return h;
}

#endif
